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<h1>v_pesq2mos
</h1>

<h2><a name="_name"></a>PURPOSE <a href="#_top"><img alt="^" border="0" src="../up.png"></a></h2>
<div class="box"><strong>V_PESQ2MOS convert PESQ speech quality scores to MOS m=(p)</strong></div>

<h2><a name="_synopsis"></a>SYNOPSIS <a href="#_top"><img alt="^" border="0" src="../up.png"></a></h2>
<div class="box"><strong>function m=v_pesq2mos(p) </strong></div>

<h2><a name="_description"></a>DESCRIPTION <a href="#_top"><img alt="^" border="0" src="../up.png"></a></h2>
<div class="fragment"><pre class="comment">V_PESQ2MOS convert PESQ speech quality scores to MOS m=(p)
Inputs:    p  is a matrix of PESQ scores

Outputs:   m  is a matrix, the same size as p, of MOS scores

 The PESQ measure is defined in [2]. The mapping function, defined in [3],
 converts raw PESQ scores (which lie in the range -0.5 to 4.5) onto the
 MOS-LQO (Mean Opinion Score - Listening Quality Objective [2]) scale in the
 range 1 to 5. The MOS scale is defined in [1] as
           5=Excellent, 4=Good, 3=Fair, 2=Poor, 1=Bad.

 Refs: [1]    ITU-T. Methods for subjective determination of transmission quality.
           Recommendation P.800, Aug. 1996.
       [2]    ITU-T. Mean opinion score (MOS) terminology.
           Recommendation P.800.1, July 2006.
       [2]    ITU-T. Perceptual evaluation of speech quality (PESQ), an objective
           method for end-to-end speech quality assessment of narrowband telephone
           networks and speech codecs. Recommendation P.862, Feb. 2001.
       [3]    ITU-T. Mapping function for transforming P.862 raw result scores to MOS-LQO.
           Recommendation P.862.1, Nov. 2003.</pre></div>

<!-- crossreference -->
<h2><a name="_cross"></a>CROSS-REFERENCE INFORMATION <a href="#_top"><img alt="^" border="0" src="../up.png"></a></h2>
This function calls:
<ul style="list-style-image:url(../matlabicon.gif)">
<li><a href="v_pesq2mos.html" class="code" title="function m=v_pesq2mos(p)">v_pesq2mos</a>	V_PESQ2MOS convert PESQ speech quality scores to MOS m=(p)</li></ul>
This function is called by:
<ul style="list-style-image:url(../matlabicon.gif)">
<li><a href="v_mos2pesq.html" class="code" title="function p=v_mos2pesq(m)">v_mos2pesq</a>	V_MOS2PESQ convert MOS speech quality scores to PESQ p=(m)</li><li><a href="v_pesq2mos.html" class="code" title="function m=v_pesq2mos(p)">v_pesq2mos</a>	V_PESQ2MOS convert PESQ speech quality scores to MOS m=(p)</li></ul>
<!-- crossreference -->


<h2><a name="_source"></a>SOURCE CODE <a href="#_top"><img alt="^" border="0" src="../up.png"></a></h2>
<div class="fragment"><pre>0001 <a name="_sub0" href="#_subfunctions" class="code">function m=v_pesq2mos(p)</a>
0002 <span class="comment">%V_PESQ2MOS convert PESQ speech quality scores to MOS m=(p)</span>
0003 <span class="comment">%Inputs:    p  is a matrix of PESQ scores</span>
0004 <span class="comment">%</span>
0005 <span class="comment">%Outputs:   m  is a matrix, the same size as p, of MOS scores</span>
0006 <span class="comment">%</span>
0007 <span class="comment">% The PESQ measure is defined in [2]. The mapping function, defined in [3],</span>
0008 <span class="comment">% converts raw PESQ scores (which lie in the range -0.5 to 4.5) onto the</span>
0009 <span class="comment">% MOS-LQO (Mean Opinion Score - Listening Quality Objective [2]) scale in the</span>
0010 <span class="comment">% range 1 to 5. The MOS scale is defined in [1] as</span>
0011 <span class="comment">%           5=Excellent, 4=Good, 3=Fair, 2=Poor, 1=Bad.</span>
0012 <span class="comment">%</span>
0013 <span class="comment">% Refs: [1]    ITU-T. Methods for subjective determination of transmission quality.</span>
0014 <span class="comment">%           Recommendation P.800, Aug. 1996.</span>
0015 <span class="comment">%       [2]    ITU-T. Mean opinion score (MOS) terminology.</span>
0016 <span class="comment">%           Recommendation P.800.1, July 2006.</span>
0017 <span class="comment">%       [2]    ITU-T. Perceptual evaluation of speech quality (PESQ), an objective</span>
0018 <span class="comment">%           method for end-to-end speech quality assessment of narrowband telephone</span>
0019 <span class="comment">%           networks and speech codecs. Recommendation P.862, Feb. 2001.</span>
0020 <span class="comment">%       [3]    ITU-T. Mapping function for transforming P.862 raw result scores to MOS-LQO.</span>
0021 <span class="comment">%           Recommendation P.862.1, Nov. 2003.</span>
0022 
0023 <span class="comment">%      Copyright (C) Mike Brookes 2012-2013</span>
0024 <span class="comment">%      Version: $Id: v_pesq2mos.m 10865 2018-09-21 17:22:45Z dmb $</span>
0025 <span class="comment">%</span>
0026 <span class="comment">%   VOICEBOX is a MATLAB toolbox for speech processing.</span>
0027 <span class="comment">%   Home page: http://www.ee.ic.ac.uk/hp/staff/dmb/voicebox/voicebox.html</span>
0028 <span class="comment">%</span>
0029 <span class="comment">%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%</span>
0030 <span class="comment">%   This program is free software; you can redistribute it and/or modify</span>
0031 <span class="comment">%   it under the terms of the GNU General Public License as published by</span>
0032 <span class="comment">%   the Free Software Foundation; either version 2 of the License, or</span>
0033 <span class="comment">%   (at your option) any later version.</span>
0034 <span class="comment">%</span>
0035 <span class="comment">%   This program is distributed in the hope that it will be useful,</span>
0036 <span class="comment">%   but WITHOUT ANY WARRANTY; without even the implied warranty of</span>
0037 <span class="comment">%   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the</span>
0038 <span class="comment">%   GNU General Public License for more details.</span>
0039 <span class="comment">%</span>
0040 <span class="comment">%   You can obtain a copy of the GNU General Public License from</span>
0041 <span class="comment">%   http://www.gnu.org/copyleft/gpl.html or by writing to</span>
0042 <span class="comment">%   Free Software Foundation, Inc.,675 Mass Ave, Cambridge, MA 02139, USA.</span>
0043 <span class="comment">%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%%</span>
0044 <span class="keyword">persistent</span> a b c d
0045 <span class="keyword">if</span> isempty(a)
0046     a=0.999;
0047     b=4.999-a;
0048     c=-1.4945;
0049     d=4.6607;
0050 <span class="keyword">end</span>
0051 <span class="keyword">if</span> nargout&gt;0
0052     m=a+b./(1+exp(c*p+d));
0053 <span class="keyword">else</span>
0054     <span class="keyword">if</span> nargin&lt;1 || isempty(p)
0055         pp=linspace(-0.5,4.5,100);
0056     <span class="keyword">else</span>
0057         pp=p;
0058     <span class="keyword">end</span>
0059     plot(pp,<a href="v_pesq2mos.html" class="code" title="function m=v_pesq2mos(p)">v_pesq2mos</a>(pp));
0060     xlabel(<span class="string">'PESQ (P.862)'</span>);
0061     ylabel(<span class="string">'Mean Opimion Score (MOS)'</span>);
0062 <span class="keyword">end</span></pre></div>
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